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2. Evaluation of genotoxicity and cytotoxicity of water samples from the Sinos River Basin, southern Brazil

Author

Bianchi, E, Goldoni, A, Trintinaglia, L, Lessing, G, Silva, CEM, Nascimento, CA, Ziulkoski, AL, Spilki, FR, and Silva, LB

Subjects
micronucleus test, cell culture, ensaio cometa, comet assay, bioensaios com peixes, cultura celular, fish bioassays, qualidade da água, water quality, teste de micronúcleo
Abstract

Some water bodies in the Sinos River Basin (SRB) have been suffering the effects of pollution by residential, industrial and agroindustrial wastewater. The presence of cytotoxic and genotoxic compounds could compromise the water quality and the balance of these ecosystems. In this context, the research aimed to evaluate the genotoxicity and cytotoxicity of the water at four sites along the SRB (in the cities of Santo Antônio da Patrulha, Parobé, Campo Bom and Esteio), using bioassays in fish and cell culture. Samples of surface water were collected and evaluated in vitro using the Astyanax jacuhiensis fish species (micronucleus test and comet assay) and the Vero lineage of cells (comet assay and cytotoxicity tests, neutral red - NR and tetrazolium MTT). The micronucleus test in fish showed no significant differences between the sampling sites, and neither did the comet assay and the MTT and NR tests in Vero cells. The comet assay showed an increase in genetic damage in the fish exposed to water samples collected in the middle and lower sections of the basin (Parobé, Campo Bom and Esteio) when compared to the upper section of the basin (Santo Antônio da Patrulha). The results indicate contamination by genotoxic substances starting in the middle section of the SRB. Alguns corpos d’água da Bacia Hidrográfica do Rio dos Sinos (BHRS) vêm sofrendo os efeitos da poluição por efluentes domésticos, industriais e agroindustriais. A presença de compostos citotóxicos e genotóxicos pode comprometer a qualidade da água e o equilíbrio desses ecossistemas. Neste contexto, o objetivo do trabalho foi avaliar a genotoxicidade e a citotoxicidade da água em quatro pontos ao longo da BHRS (Santo Antônio da Patrulha, Parobé, Campo Bom e Esteio), utilizando bioensaios em peixes e em cultura celular. As amostras de água de superfície foram coletadas e avaliadas in vitro utilizando a espécie de peixe Astyanax jacuhiensis (teste de micronúcleo e ensaio cometa) e a linhagem celular tipo Vero (ensaio cometa e os testes de citotoxicidade vermelho neutro - VN e tetrazólio MTT). O teste de micronúcleos em peixes não apresentou diferenças significativas entre os pontos de coleta, assim como o ensaio cometa e os testes VN e MTT nas células Vero. O ensaio cometa demonstrou aumento nos danos genéticos em peixes expostos às amostras de água coletadas nos trechos médio e inferior da bacia (Parobé, Campo Bom e Esteio) em relação ao trecho superior da bacia (Santo Antônio da Patrulha). Os resultados indicam contaminação por substâncias genotóxicas a partir do trecho médio da BHRS.

Published
2015

3. Cytotoxicity assays as tools to assess water quality in the Sinos River basin

Author

Trintinaglia, L, Bianchi, E, Silva, LB, Nascimento, CA, Spilki, FR, and Ziulkoski, AL

Subjects
Sinos River basin, cytotoxicity, samples preparation, citotoxicidade, preparação de amostras, bacia do Rio do Sinos
Abstract

Cytotoxicity assays using cell cultures may be an alternative to assess biological toxicity of surface waters and may help to improve the control of water quality. This study compared two methods to prepare culture media for the exposure of Hep-2 cells to water samples collected from the Rolante River, an important affluent of the Sinos River. The toxicity was evaluated using the MTT and neutral red assays. Two methods were used to prepare culture media. In method 1, the sample was diluted at 1:1, 1:10, 1:100, 1:1000, 1:10.000 (v/v, sample/medium) in a standard culture medium; in method 2, water samples were used as the solvent for the culture medium, which was prepared at concentrations of 100, 80, 60, 40 and 20%. Semi-confluent cultures were then exposed to the media test for 24 hours, and cytotoxicity was determined immediately using the MTT and NR assays. Mitochondrial activity (MTT) was significantly lower at all concentrations in both methods, except at 1:1000 in method 1. However, the lysosome viability (NR) results revealed cytotoxicity only in the 1:1 sample of method 1. Both culture preparation methods were efficient and sensitive to the MTT assay, but method 2 seemed to be more adequate for the NR assay. The Rolante River has cytotoxic contaminants to Hep-2 cells, which may be one of the explanations for the poor water quality of the Sinos River basin. Os ensaios de citotoxicidade utilizando culturas de células constituem uma alternativa para avaliar a toxicidade biológica de águas de superfície e podem auxiliar no controle da qualidade da água. Este estudo comparou dois métodos de preparação dos meios de cultura com amostras de água coletadas no rio Rolante, um importante afluente do Rio dos Sinos, para a exposição de células Hep-2. A toxicidade foi avaliada usando os ensaios do MTT e do vermelho neutro (VN). Dois métodos foram utilizados para preparar os meios de cultura. No método 1, a amostra foi diluída a 1:1, 1:10, 1:100, 1:1000 e 1:10.000 (v/v, amostra/ meio de cultivo) em um meio de cultura padrão; no método 2, as amostras de água foram utilizados como solventes para o meio de cultura, o qual foi preparado em concentração de 100% e nas diluições de 80, 60, 40 e 20%. Culturas semi-confluentes foram então expostas aos meios teste durante 24 horas, e a citotoxicidade foi determinada imediatamente usando os ensaios MTT e VN. A atividade mitocondrial (MTT) foi significativamente menor em todas as concentrações em ambos os métodos, exceto na diluição 1:1000 do método 1. No entanto, os resultados de viabilidade lisossomal (VN) revelaram citotoxicidade apenas no na diluição 1:1 do método 1. Ambos os métodos de preparação do meio cultura foram eficientes e sensíveis para o ensaio do MTT, mas o método 2 foi mais adequado para o ensaio do VN. O rio Rolante possui contaminantes citotóxicos para as células Hep-2, o que pode ser uma das explicações para a baixa qualidade da água da Bacia do Rio dos Sinos.

Published
2015

6. Evaluation of phytotoxicity of municipal landfill leachate before and after biological treatment

Author

Klauck, CR, Rodrigues, MAS, and Silva, LB

Subjects
water pollution, wastewater treatment, bioensaios com plantas, efeitos tóxicos, toxic effects, poluição da água, tratamento de efluentes, plant bioassays
Abstract

In the present study, leachate toxicity of a municipal solid waste landfill located in the Sinos River Valley region (southern Brazil) was evaluated using plant bioassays. Leachate toxicity was assessed by analysis of seed germination and root elongation of lettuce (Lactuca sativa L.) and rocket plant (Eruca sativa Mill.) and root elongation of onions (Allium cepa L.). Bioassays were performed by exposing the seeds of L. sativa and E. sativa and the roots of A. cepa to raw leachate, treated leachate (biological treatment) and negative control (tap water). The levels of metals detected in both samples of leachate were low, and raw leachate showed high values for ammoniacal nitrogen and total Kjeldahl nitrogen. There is a reduction in the values of several physicochemical parameters, which demonstrates the efficiency of the treatment. Both L. sativa and A. cepashowed a phytotoxic response to landfill leachate, showing reduced root elongation. However, the responses of these two plant species were different. Root elongation was significantly lower in A. cepa exposed to treated leachate, when compared to negative control, but did not show any difference when compared to raw leachate. In L. sativa, seeds exposed to the raw leachate showed significant reduction in root elongation, when compared to treated leachate and negative control. Seed germination showed no difference across the treatments. The results of the study show that plant species respond differently and that municipal solid waste landfill leachate show phytotoxicity, even after biological treatment. No presente trabalho, a toxicidade do lixiviado (chorume) de um aterro sanitário municipal, localizado na região do Vale do Rio dos Sinos, foi avaliada utilizando bioensaios em plantas. A toxicidade do chorume foi analisada pelo teste de germinação e crescimento radicular de alface (Lactuca sativa L.) e rúcula (Eruca sativa Mill.) e pelo teste de crescimento radicular em cebola (Allium cepa L.). Os bioensaios foram realizados com a exposição de sementes de L. sativa e E. sativa e raízes de A. cepa a amostras de chorume bruto, tratado por processo biológico e controle negativo (água de abastecimento público). Os níveis de metais detectados nas amostras de chorume foram baixos, e o chorume bruto apresentou valores elevados de nitrogênio amoniacal e nitrogênio Kjeldahl total. Ocorreu redução nos valores de vários parâmetros físico-químicos, demonstrando a eficiência do tratamento biológico. Os resultados indicam fitotoxicidade do chorume em L. sativa e A. cepa, evidenciada pela redução do crescimento radicular. Entretanto, as respostas destas duas espécies diferiram. O crescimento radicular foi significativamente inferior em A. cepa exposta ao chorume tratado quando comparado ao controle negativo, mas não apresentou diferença quando comparado ao chorume bruto. Em L. sativa, a exposição das sementes ao chorume bruto causou redução no crescimento radicular quando comparado com o chorume tratado e controle negativo. Não foram observadas diferenças entre os tratamentos para o parâmetro germinação de sementes. Os resultados deste trabalho indicam que as espécies de plantas estudadas são diferentes em suas respostas e que o chorume apresenta toxicidade, mesmo após o tratamento biológico.

Published
2015

7. Moving beyond classical markers of water quality: detection of enteric viruses and genotoxicity in water of the Sinos River

Author

Bergamaschi, B, Rodrigues, MT, Silva, JVS, Kluge, M, Luz, RB, Fleck, JD., Bianchi, E, Silva, LB, and Spilki, FR

Subjects
rotavirus, rotavírus, genotoxicity, adenovirus, adenovírus, genotoxicidade, enterovírus, qualidade da água, water quality, enteroviruses
Abstract

It is well recognized that the classical biological and chemical markers of environmental pollution do not necessarily indicate the presence or absence of emerging threats to public health, such as waterborne viruses and genotoxicants. The purpose of this preliminary study was to evaluate the presence of material of enteroviruses (EV), rotavirus (RV) and adenovirus (AdV) and genotoxicity in water samples from points of routine monitoring of water quality in the main course of the Sinos River. The points are classified into different levels of pollution in accordance to the Brazilian federal regulations. Viral genomes from EV, AdV were detected in two of the 4 collection points regardless of the level of urbanisation of the surrounding areas. In contrast, genotoxicity was not observed in piava (Leporinus obtusidens) fingerlings cultivated on these same water samples. Results were compared with classical physical, chemical and microbiological parameters. There was no clear evidence of association between any of the classical markers and the presence of viral genomes in the water samples tested. É amplamente reconhecido que os marcadores biológicos e químicos clássicos para a poluição ambiental não necessariamente indicam a presença ou ausência de ameaças emergentes à saúde pública, tais como vírus transmitidos pela água e genotoxicantes. Este estudo preliminar teve por objetivo detectar material genético de enterovírus (EV), rotavírus (RV) e adenovírus (AdV) e genotoxicidade em amostras de água de pontos de monitoramento de rotina da qualidade da água no curso principal do rio dos Sinos. Os pontos são classificados em níveis diferentes de poluição, de acordo com as normativas federais brasileiras. Genomas virais de EV, RV e RV foram detectados em dois dos quatro pontos de coleta, independente do nível de urbanização das áreas adjacentes. Por outro lado, não foi observada genotoxicidade em alevinos de piava (Leporinus obtusidens) cultivados nestas mesmas amostras de água. Os resultados são comparados com marcadores físicos, químicos e microbiológicos clássicos, não há nenhuma evidência clara da associação entre qualquer um dos marcadores clássicos e da presença de genomas virais nas amostras de água testadas.

Published
2015

8. Acoustical Comfort in Primary School Classrooms in the City of Joao Pessoa, Paraiba, Brazil

Author

Silva Lb and Santos Rls

Subjects
Background noise, Engineering, Reverberation, business.industry, Reference values, Speech recognition, Applied psychology, Normative, Intelligibility (communication), business
Abstract

Based on Brazilian and International normative guidelines, acoustical comfort was evaluated in 119 primary school classrooms in the City of Joao Pessoa (Brazil). A Beta Regression Model (BRM) was built, through which it was verified to what extent acoustic parameters of these rooms can affect teacher speech intelligibility. It was found that the Levels of Noise from external sources, Background Noise, Reverberation Time and the Speech Intelligibility Index are not within reference values established by the norms. Reverberation Time affects the quality of intelligibility at around 77.18%.

Published
2013

9. Exploring the Utility of the NEO-PI-R in a Sample of South African University Students

Author

e Silva, LB and Laher, S

Subjects
culture, Five Factor Model, language bias, NEO-PI-R, personality
Abstract

The Five Factor Model (FFM) of personality is currently amongst the most widely accepted theories in personality psychology and the Revised NEO Personality Inventory (NEO-PI-R) is one of the best operationalisations of this model. Research indicates that the FFM is not wholly applicable in African cultures (Laher, 2008). Thus this study explored the utility of the NEO-PI-R in a sample of 17 postgraduate students from the University of the Witwatersrand using a mixed methods approach. A non-experimental cross-sectional design was used to determine which items of the NEO-PI-R are culturally and linguistically inappropriate. A questionnaire incorporating the NEO-PI-R, demographic information; namely age, gender, population group and home language, and open-ended questions were used. 28.75% (69 out of 240) of the items of the NEO-PI-R were found to be culturally inappropriate in the study by more than 10% of the sample. These items were primarily from the Openness to Experience, Extraversion and Agreeableness domains. 43.33% (104 out of 240) of the items were found to be linguistically problematic in the study by more than 10% of the sample. These items were primarily from the Openness to Experience and Neuroticism domains. A focus group was conducted with 5 of the 17 postgraduate students. A thematic content analysis conducted on the focus group session revealed 6 themes in terms of the utility of the NEO-PI-R, namely, language, culture, psychometric testing, dynamic vs. static nature of personality and social desirability.

Published
2012

10. Comparative analysis of the leaf anatomy in two Parodiolyra species (Poaceae: Olyreae) occurring on forests in Eastern Brazil

Author

Jesus Junior, LA, Oliveira, RP, Leite, KRB, and Silva, LB

Subjects
bambusoideae, specific delimitation, bambus herbaceous, delimitação específica, herbaceous bamboos, microscopic characters, caracteres microscópicos
Abstract

Parodiolyra is a member of Olyreae, a tribe of herbaceous bamboo species within the Poaceae. The genus has five species, four of which were previously regarded as belonging to Olyra L. Parodiolyra has a Neotropical distribution and only two species occur on forests in Eastern Brazil: P. micrantha (Kunth) Zuloaga & Davidse and P. ramosissima (Trin.) Soderstr. & Zuloaga, the first widely distributed in the Neotropics while the second is endemic to the state of Bahia. Leaf anatomy of the two species was analysed with the aid of an optical microscope. The objective was to describe the microscopic characters and evaluate if they can be useful for the taxonomy of the genus. The observed anatomical structures did not differ from other genera of herbaceous bamboos, however some characters, both from the mesophyll and the epidermis, were useful to delimit the two species. Parodiolyra está inserido em Olyreae, tribo de bambus herbáceos pertencente à Poaceae, e apresenta cinco espécies, sendo quatro delas previamente consideradas como parte de Olyra L. O gênero tem distribuição neotropical e apenas duas espécies ocorrem nas florestas do leste do Brasil: P. micrantha (Kunth) Zuloaga & Davidse e P. ramosissima (Trin.) Soderstr. & Zuloaga; a primeira, amplamente distribuída no Neotrópico, e a última, endêmica do Estado da Bahia. A anatomia foliar dessas duas espécies foi analisada através de microscopia de luz, com o objetivo de descrever seus caracteres microscópicos e avaliar se os mesmos podem ser úteis para a taxonomia do gênero. A estrutura anatômica observada não se diferencia daquela dos demais gêneros de bambus herbáceos, mas alguns caracteres do mesofilo e da epiderme foram úteis para delimitar as duas espécies.

Published
2012

11. Prepulse technique for producing low-ZNe-like x-ray lasers

Author

Joseph Nilsen, Juan C. Moreno, Da Silva Lb, and B. J. MacGowan

Subjects
Physics, X-ray, chemistry.chemical_element, Laser, Atomic and Molecular Physics, and Optics, Charged particle, Ion, law.invention, Neon, chemistry, law, Stimulated emission, Atomic physics, Lasing threshold, Prepulse inhibition
Abstract

We report an application of the prepulse technique which uses a low-intensity prepulse before the main optical drive pulse to prepare the plasma prior to lasing in low-[ital Z], Ne-like ions. Ne-like x-ray lasers are now available over a previously inaccessible range of wavelengths. As an illustration of this technique we report an observation of lasing in Cr[sup 14+] and Fe[sup 16+] on the Ne-like [ital J]=0[r arrow]1, 3[ital p][r arrow]3[ital s] transitions at 285 and 255 A as well as gain measurements for Ti[sup 12+].

Published
1993

12. Evaluation of Sinos River water genotoxicity using the comet assay in fish

Author

Scalon, MCS., Rechenmacher, C., Siebel, AM., Kayser, ML., Rodrigues, MT., Maluf, SW., Rodrigues, MAS., and Silva, LB

Subjects
biomarcadores, metais, genotoxicity, biomarkers, metals, river pollution, genotoxicidade, poluição de rios
Abstract

The Sinos River, in southern Brazil, is polluted by industrial discharges and untreated urban wastes. Fish genotoxicity biomarkers are valuable parameters for environmental risk assessment. In this study, we used the comet assay to detect genotoxicity due to multiple sources of pollution in the peripheral blood of a native fish species (Hyphessobrycon luetkenii). In addition, we analysed possible DNA damage from aluminum, lead, chromium, copper, nickel, iron and zinc contamination. Water samples were collected seasonally from three sampling sites and the fish were assessed under laboratory conditions. Water chemical analysis showed an increased level of aluminum and iron in most of the samples at sites 2 and 3, located in the middle and lower river course, respectively. The index of DNA damage assessed by the comet assay demonstrated no significant differences in different seasons or at the different sampling sites, while the frequency of cells with DNA damage was higher in water samples collected at sites 1 and 2 during the spring season. None of the metals studied seems to be associated with the increase in the frequency of cells with DNA damage observed during the spring season. The results of this study indicate that the Sinos River is contaminated with substances that are genotoxic to fish, including the waters near the river spring. O rio dos Sinos, no sul do Brasil, é poluído tanto por descargas industriais como por resíduos urbanos não tratados. Os biomarcadores de genotoxicidade em peixes são parâmetros valiosos para a determinação de risco ambiental. Neste estudo, utilizamos o ensaio cometa em sangue periférico de um peixe nativo (Hyphessobrycon luetkenii) para detectar a genotoxicidade devido a múltiplas fontes de poluição. Além disso, analisamos a possível influência da contaminação por alumínio, chumbo, cromo, cobre, níquel, ferro e zinco sobre o dano de DNA. Amostras de água foram coletadas sazonalmente em três pontos de coleta e os peixes foram expostos sob condições de laboratório. A análise química da água mostrou níveis elevados de alumínio e ferro na maioria das amostras dos pontos 2 e 3, localizados nos cursos médio e inferior do rio, respectivamente. O índice de dano de DNA estimado pelo ensaio cometa não demonstrou diferenças significativas tanto entre estações como entre pontos de coleta, enquanto que a frequência de células com dano de DNA apresentou valores superiores nas amostras de água coletadas durante a primavera nos pontos 1 e 2. Nenhum dos metais estudados parece estar associado com o aumento na frequência de células com dano de DNA observado durante a primavera. Os resultados deste estudo indicam que o rio dos Sinos está contaminado com substâncias genotóxicas para os peixes, incluindo as águas próximas à nascente do rio.

Published
2010

13. Análise de múltiplos biomarcadores em ratos para determinar o impacto da poluição do Rio dos Sinos

Author

Rechenmacher,C., Siebel,AM., Goldoni,A., Klauck,CR., Sartori,T., Rodrigues,MT., Rodrigues,MAS., Gehlen,G., Ardenghi,PG., and Silva,LB

Subjects
estresse oxidativo, biomarcadores, genotoxicity, tissue damage, dano tecidual, pollution, biomarkers, oxidative stress, genotoxicidade, poluição
Abstract

The aim of this study was to determine the feasibility of combining water quality analysis with different biomarkers to characterise the relationship between anthropogenic contamination and biotic response in the Sinos River, southern Brazil. Wistar rats were studied using three biomarkers combined with physical, chemical and microbiological analysis to assess the effects of pollution at four sampling sites. The induction of oxidative stress was quantified by MDA levels in peripheral blood, lymphocyte DNA damage was determined using the comet assay, and histopathological changes were analysed in the liver. After sampling, animals were allowed to drink the river water during a 48 hours period. No increase in oxidative stress and DNA damage was observed. However, liver damage was observed in the animals exposed to water samples, indicating that the Sinos River is contaminated with hepatotoxic substances. Water analyses confirmed that water quality decreased downriver. O objetivo deste estudo foi determinar a viabilidade de combinar a análise da qualidade da água com o estudo de biomarcadores para caracterizar a relação entre contaminação antropogênica e resposta biótica no rio dos Sinos, sul do Brasil. Ratos Wistar machos foram estudados usando três biomarcadores combinados com análises físicas, químicas e microbiológicas para determinar os efeitos da poluição em quatro locais de amostragem de água. A indução do estresse oxidativo foi quantificada pelos níveis de MDA no sangue periférico, o dano do DNA linfocitário foi determinado usando o ensaio cometa, e as alterações histopatológicas foram analisadas no fígado. As amostras da água do rio dos Sinos (dos quatro pontos selecionados) foram administradas por via oral (como água para beber) por 48 horas. Nenhum aumento do estresse oxidativo ou do dano do DNA foi observado. Entretanto, dano do tecido hepático foi verificado nos animais expostos à ingestão das amostras da água, indicando que o rio dos Sinos está contaminado com substâncias hepatotóxicas. As análises das amostras de água confirmaram a redução da qualidade da água em direção à foz do rio.

Published
2010

25. Leptospiral immunoglobulin-like proteins interact with human complement regulators factor H, FHL-1, FHR-1, and C4BP.

Author

Castiblanco-Valencia MM, Fraga TR, Silva LB, Monaris D, Abreu PA, Strobel S, Józsi M, Isaac L, Barbosa AS, Castiblanco-Valencia, Mónica Marcela, Fraga, Tatiana Rodrigues, Silva, Ludmila Bezerra da, Monaris, Denize, Abreu, Patrícia Antônia Estima, Strobel, Stefanie, Józsi, Mihály, Isaac, Lourdes, and Barbosa, Angela Silva

Abstract

Leptospira, the causative agent of leptospirosis, interacts with several host molecules, including extracellular matrix components, coagulation cascade proteins, and human complement regulators. Here we demonstrate that acquisition of factor H (FH) on the Leptospira surface is crucial for bacterial survival in the serum and that these spirochetes, besides interacting with FH, FH related-1, and C4b binding protein (C4BP), also acquire FH like-1 from human serum. We also demonstrate that binding to these complement regulators is mediated by leptospiral immunoglobulin-like (Lig) proteins, previously shown to interact with fibronectin, laminin, collagen, elastin, tropoelastin, and fibrinogen. Factor H binds to Lig proteins via short consensus repeat domains 5 and 20. Competition assays suggest that FH and C4BP have distinct binding sites on Lig proteins. Moreover, FH and C4BP bound to immobilized Ligs display cofactor activity, mediating C3b and C4b degradation by factor I. In conclusion, Lig proteins are multifunctional molecules, contributing to leptospiral adhesion and immune evasion. [ABSTRACT FROM AUTHOR]

Published
2012
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26. Functional capacity in elderly in the community and interventions proposed in the team health.

Author

Nakatani AYK, da Silva LB, Bachion MM, and Nunes DP

Abstract

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Published
2009

27. Identification of Novel Chemical Entities for Adenosine Receptor Type 2A Using Molecular Modeling Approaches

Author

Rosivaldo S. Borges, Luciane B. Silva, Jorddy Neves Cruz, Sirlene S. B. Ota, Kelton L. B. Santos, Franco Henrique Andrade Leite, Moysés Fagundes de Araújo Neto, Carlos Henrique Tomich de Paula da Silva, Ryan da Silva Ramos, Joaquín M. Campos, Cleison C. Lobato, Cleydson B. R. Santos, [Dos Santos,KLB, Cruz,JN, Silva,LB, Ramos,RS, Lobato,CC, Borges,RS, Santos,CBR] Laboratory of Modeling and Computational Chemistry, Department of Biological and Health Sciences, Federal University of Amapá, Macapá-AP, Brazil. [Dos Santos,KLB, Ota,SSB, Santos,CBR] Nucleus of Studies and Selection of Bioactive Molecules, Institute of Health Sciences, Federal University of Pará, Belém-PA, Brazil. [Neto,MFA, Leite,FHA, and ] Laboratory of Molecular Modeling, State University of Feira de Santana, Feira de Santana, Bahia, Brazil. [da SIlva,CHTP] Computational Laboratory of Pharmaceutical Chemistry, University of São Paulo, Ribeirão Preto-SP, Brazil. [da SIlva,CHTP] Department of Chemistry, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil. [Campos,JM] Department of Pharmaceutical and Organic Chemistry, Faculty of Pharmacy, Institute of Biosanitary, Research ibs. Granada, University of Granada, Granada, Spain.

Subjects
Adenosine, Molecular model, Pharmaceutical Science, Quantitative Structure-Activity Relationship, Relación estructura-actividad cuantitativa, Ligands, Chemicals and Drugs::Chemical Actions and Uses::Specialty Uses of Chemicals::Laboratory Chemicals::Ligands [Medical Subject Headings], Analytical Chemistry, Phenomena and Processes::Chemical Phenomena::Biochemical Phenomena::Structure-Activity Relationship::Quantitative Structure-Activity Relationship [Medical Subject Headings], Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Primates::Haplorhini::Catarrhini::Hominidae::Humans [Medical Subject Headings], Molecular dynamics, Simulación del acoplamiento molecular, Drug Discovery, Agonistas del receptor de adenosina A2, 0303 health sciences, Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Models, Theoretical::Models, Molecular::Molecular Dynamics Simulation [Medical Subject Headings], Chemistry, Biological activity, Chemicals and Drugs::Heterocyclic Compounds::Heterocyclic Compounds, 2-Ring::Purines::Purine Nucleosides::Adenosine [Medical Subject Headings], Molecular Docking Simulation, INDÚSTRIA FARMACÊUTICA, Cribado sistemático, Chemistry (miscellaneous), Molecular Medicine, BindingDB, Pharmacophore, Virtual screening, Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Proteins::Membrane Proteins::Receptors, Cell Surface::Receptors, Purinergic::Receptors, Purinergic P1::Receptors, Adenosine A2 [Medical Subject Headings], Quantitative structure–activity relationship, Adenosine A2 Receptor Agonists, 030303 biophysics, Computational biology, Adenosine A2A receptor, Molecular Dynamics Simulation, Article, Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Models, Theoretical::Models, Molecular::Molecular Docking Simulation [Medical Subject Headings], Chemicals and Drugs::Chemical Actions and Uses::Pharmacologic Actions::Molecular Mechanisms of Pharmacological Action::Neurotransmitter Agents::Purinergic Agents::Purinergic Agonists::Purinergic P1 Receptor Agonists::Adenosine A2 Receptor Agonists [Medical Subject Headings], lcsh:QD241-441, 03 medical and health sciences, lcsh:Organic chemistry, Molecular insight, Humans, Physical and Theoretical Chemistry, 030304 developmental biology, Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Proteins::Membrane Proteins::Receptors, Cell Surface::Receptors, Purinergic::Receptors, Purinergic P1 [Medical Subject Headings], adenosine A2A receptor, Receptors, Adenosine A2, Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Models, Theoretical::Models, Statistical::Linear Models [Medical Subject Headings], Organic Chemistry, virtual screening, Simulación de Dinámica Molecular, Docking (molecular), molecular insight
Abstract

Adenosine Receptor Type 2A (A2AAR) plays a role in important processes, such as anti-inflammatory ones. In this way, the present work aimed to search for compounds by pharmacophore-based virtual screening. The pharmacokinetic/toxicological profiles of the compounds, as well as a robust QSAR, predicted the binding modes via molecular docking. Finally, we used molecular dynamics to investigate the stability of interactions from ligand-A2AAR. For the search for A2AAR agonists, the UK-432097 and a set of 20 compounds available in the BindingDB database were studied. These compounds were used to generate pharmacophore models. Molecular properties were used for construction of the QSAR model by multiple linear regression for the prediction of biological activity. The best pharmacophore model was used by searching for commercial compounds in databases and the resulting compounds from the pharmacophore-based virtual screening were applied to the QSAR. Two compounds had promising activity due to their satisfactory pharmacokinetic/toxicological profiles and predictions via QSAR (Diverset 10002403 pEC50 = 7.54407; ZINC04257548 pEC50 = 7.38310). Moreover, they had satisfactory docking and molecular dynamics results compared to those obtained for Regadenoson (Lexiscan®), used as the positive control. These compounds can be used in biological assays (in vitro and in vivo) in order to confirm the potential activity agonist to A2AAR, PROPESP/UFPA, National Council for Scientific and Technological Development (CNPq)

Published
2020

28. ART with or without the aid of chemo-mechanical agents: a systematic review.

Author

da Silva LB, Magno MB, Fonseca-Gonçalves A, and Pintor AVB

Subjects
Humans, Quality of Life, Dental Atraumatic Restorative Treatment methods, Dental Caries therapy
Abstract

Objectives: To investigate whether the use of chemo-mechanical carious tissue removal (CMCTR) agents is effective for Atraumatic Restorative Treatment (ART)., Materials and Methods: Searches were conducted in 6 databases for inclusion of clinical studies. Risk of bias was assessed (RoB 2 and ROBINS-I), a meta-analysis was performed with data from time of carious tissue removal (TCTR), and the certainty of evidence was estimated. ART + CMCTR was compared to ART for the treatment of caries lesions in primary teeth (pt) and permanent teeth (PT) of humans, considering acceptability, pain/discomfort, survival and success of restorations (SSR), Oral Health-Related Quality of life (OHRQol), satisfaction, TCTR, total treatment time (TTT), carious tissue removal efficacy and adverse effects., Results: Of 12 included studies, 4 showed low risk of bias, considering pain, TTT and TCTR outcomes. ART + CMCTR was similar or more accepted than ART for pt, causing similar or less pain/discomfort for both dentitions. There was no difference in SSR, OHRQol for PT, and adverse effects (pt), although greater satisfaction was reported after ART + CMCTR in case of PT. ART + CMCTR was better or as effective as ART in removing carious tissue (pt). TTT for pt was divergent between the groups, but without difference of TCTR for both, pt and PT (MD 0.11 [-1.56, 1.77] p = 0.90, I 2 =93%)., Conclusions: In general, ART + CMCTR is effective, providing greater satisfaction, with no difference in SSR, OHRQol and adverse effects compared to ART, which did not present advantages in relation to pain/discomfort and efficacy in removing carious tissue. The TTT was influenced by the CMCTR agent; however, there was no difference for TCTR in the overall quantitative synthesis with Papacárie DuoGel ® ., Clinical Relevance: The use of chemo-mechanical agents for carious tissue removal in the ART may benefit patients with reduced pain/discomfort., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Published
2024
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29. Oxidative stress modulating nanomaterials and their biochemical roles in nanomedicine.

Author

Patel KD, Keskin-Erdogan Z, Sawadkar P, Nik Sharifulden NSA, Shannon MR, Patel M, Silva LB, Patel R, Chau DYS, Knowles JC, Perriman AW, and Kim HW

Subjects
Humans, Animals, Oxidation-Reduction, Neoplasms drug therapy, Neurodegenerative Diseases drug therapy, Oxidative Stress drug effects, Nanomedicine methods, Nanostructures chemistry, Nanostructures therapeutic use, Reactive Oxygen Species metabolism
Abstract

Many pathological conditions are predominantly associated with oxidative stress, arising from reactive oxygen species (ROS); therefore, the modulation of redox activities has been a key strategy to restore normal tissue functions. Current approaches involve establishing a favorable cellular redox environment through the administration of therapeutic drugs and redox-active nanomaterials (RANs). In particular, RANs not only provide a stable and reliable means of therapeutic delivery but also possess the capacity to finely tune various interconnected components, including radicals, enzymes, proteins, transcription factors, and metabolites. Here, we discuss the roles that engineered RANs play in a spectrum of pathological conditions, such as cancer, neurodegenerative diseases, infections, and inflammation. We visualize the dual functions of RANs as both generator and scavenger of ROS, emphasizing their profound impact on diverse cellular functions. The focus of this review is solely on inorganic redox-active nanomaterials (inorganic RANs). Additionally, we deliberate on the challenges associated with current RANs-based approaches and propose potential research directions for their future clinical translation.

Published
2024
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30. NONO2P, a novel nitric oxide donor, causes vasorelaxation through NO/sGC/PKG pathway, K + channels opening and SERCA activation.

Author

Moraes RA, Brito DS, Araujo FA, Jesus RLC, Silva LB, Sá DS, Silva da Silva CD, Pernomian L, Wenceslau CF, Priviero F, Webb RC, and Silva DF

Subjects
Animals, Male, Rats, Mesenteric Arteries drug effects, Mesenteric Arteries physiology, Guanylate Cyclase metabolism, Enzyme Activation drug effects, Vasodilation drug effects, Nitric Oxide Donors pharmacology, Rats, Wistar, Nitric Oxide metabolism, Soluble Guanylyl Cyclase metabolism, Sarcoplasmic Reticulum Calcium-Transporting ATPases metabolism, Potassium Channels metabolism, Cyclic GMP-Dependent Protein Kinases metabolism, Cyclic GMP metabolism, Signal Transduction drug effects
Abstract

Background & Aims: The treatment of cardiovascular diseases (CVD) could greatly benefit from using nitric oxide (NO) donors. This study aimed to investigate the mechanisms of action of NONO2P that contribute to the observed responses in the mesenteric artery. The hypothesis was that NONO2P would have similar pharmacological actions to sodium nitroprusside (SNP) and NO., Methods: Male Wistar rats were euthanized to isolate the superior mesenteric artery for isometric tension recordings. NO levels were measured using the DAF-FM/DA dye, and cyclic guanosine monophosphate (cGMP) levels were determined using a cGMP-ELISA Kit., Results: NONO2P presented a similar maximum efficacy to SNP. The free radical of NO (NO • ) scavengers (PTIO; 100 μM and hydroxocobalamin; 30 μM) and nitroxyl anion (NO - ) scavenger (L-cysteine; 3 mM) decreased relaxations promoted by NONO2P. The presence of the specific soluble guanylyl cyclase (sGC) inhibitor (ODQ; 10 μM) nearly abolished the vasorelaxation. The cGMP-dependent protein kinase (PKG) inhibition (KT5823; 1 μM) attenuated the NONO2P relaxant effect. The vasorelaxant response was significantly attenuated by blocking inward rectifying K + channels (K ir ), voltage-operated K + channels (K V ), and large conductance Ca 2+ -activated K + channels (BK Ca ). NONO2P-induced relaxation was attenuated by cyclopiazonic acid (10 μM), indicating that sarcoplasmic reticulum Ca2+-ATPase (SERCA) activation is involved in this relaxation. Moreover, NONO2P increased NO levels in endothelial cells and cGMP production., Conclusions: NONO2P induces vasorelaxation with the same magnitude as SNP, releasing NO • and NO - . Its vasorelaxant effect involves sGC, PKG, K + channels opening, and SERCA activation, suggesting its potential as a therapeutic option for CVD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Published
2024
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31. The influence of tonality, tempo, and musical sophistication on the listener's time-duration estimates.

Author

Silva LB, Phillips M, and Martins JO

Subjects
Humans, Female, Male, Young Adult, Adult, Analysis of Variance, Auditory Perception physiology, Pitch Perception physiology, Adolescent, Music, Time Perception physiology, Acoustic Stimulation
Abstract

Music listening affects time perception, with previous studies suggesting that a variety of factors may influence this: musical, individual, and environmental. Two experiments investigated the effect of musical factors (tonality and musical tempo) and individual factors (a listener's level of musical sophistication) on subjective estimates of duration. Participants estimated the duration of different versions of newly composed instrumental music stimuli under retrospective and prospective conditions. Stimuli varied in tempo (90-120 bpm) and tonality (tonal-atonal), in a 2 × 2 factorial design, while other musical parameters remained constant. Estimates were made using written estimates of minutes and seconds in Experiment 1, and the reproduction method in Experiment 2. Two-way analyses of variance (ANOVAs) showed no main effect of tonality on estimates and no significant interactions between tempo and tonality, under any condition. Musical tempo significantly affected estimates, with the faster tempo leading to longer estimates, but only in the prospective condition, and with the use of the reproduction method. Correlation matrices using the Pearson correlation coefficient found no correlation between musical sophistication scores (measured using the Goldsmiths Musical Sophistication Index [Gold-MSI]) and verbal or reproduction estimates. In conclusion, together with the existing literature, findings suggest that (1) changes in tonality, without further changes in rhythm, metre, or melodic contour, do not significantly affect estimates; (2) small changes in musical tempo influence only prospective reproduction estimates, with larger tempo differences or longer stimuli being needed to cause changes in retrospective estimates; (3) participants' level of musical sophistication does not impact estimates of musical duration; and (4) empirical research on music listening and subjective time must consider potential method-dependent results., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Published
2024
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32. EFFICACY AND SAFETY OF ONE ANASTOMOSIS GASTRIC BYPASS IN SURGICAL TREATMENT OF OBESITY: SYSTEMATIC REVIEW AND META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS.

Author

Onzi TR, Salgado Júnior W, Bastos ELS, Dantas ACB, Silva LB, Oliveira Neto AA, Tristão LS, Santos CLD, Bernardo WM, and Chavez MP

Subjects
Humans, Anastomosis, Surgical adverse effects, Anastomosis, Surgical methods, Obesity, Morbid surgery, Randomized Controlled Trials as Topic, Treatment Outcome, Gastric Bypass methods, Gastric Bypass adverse effects
Abstract

Background: One anastomosis gastric bypass (OAGB) has gained prominence in the search for better results in bariatric surgery. However, its efficacy and safety compared to Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) remain ill-defined., Aims: To compare the efficacy and safety of OAGB relative to RYGB and SG in the treatment of obesity., Methods: We systematically searched PubMed, EMBASE, Cochrane Library, Lilacs, and Google Scholar databases for randomized controlled trials comparing OAGB with RYGB or SG in the surgical approach to obesity. We pooled outcomes for body mass index, percentage of excess weight loss, type-2 diabetes mellitus remission, complications, and gastroesophageal reflux disease. Statistical analyses were performed with R software (version 4.2.3)., Results: Data on 854 patients were extracted from 11 randomized controlled trials, of which 422 (49.4%) were submitted to OAGB with mean follow-up ranging from six months to five years. The meta-analysis revealed a significantly higher percentage of excess weight loss at 1-year follow-up and a significantly lower body mass index at 5-year follow-up in OAGB patients. Conversely, rates of type-2 diabetes mellitus remission, complications, and gastroesophageal reflux disease were not significantly different between groups. The overall quality of evidence was considered very low., Conclusions: Our results corroborate the comparable efficacy of OAGB in relation to RYGB and SG in the treatment of obesity, maintaining no significant differences in type-2 diabetes mellitus remission, complications, and gastroesophageal reflux disease rates.

Published
2024
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33. Difficult fetal extraction in cesarean section: Number 8 - 2024.

Author

Alves ÁLL, Nozaki AM, and da Silva LB

Subjects
Female, Humans, Infant, Newborn, Pregnancy, Fetus surgery, Head, Cesarean Section
Abstract

The main causes of difficult fetal extraction during cesarean section are deeply impacted fetal head and floating presentation of the fetus. Studies of management techniques for difficult fetal extraction during cesarean section and the maternal and neonatal results lack scientific evidence, as these predominantly come from case reports, small case series and expert opinions. The deeply impacted fetal head is usually associated with prolongation of the expulsion period and/or unsuccessful attempts at operative vaginal delivery. The main maternal complications associated with the management of the deeply impacted fetal head are lacerations in the lower uterine segment, hematomas in the uterine ligaments and injuries to the uterine vessels, cervix and/or urinary tract. The main neonatal complications associated with the management of a deeply impacted fetal head are intracranial hemorrhage, fractures of the skull and/or cervical spine, nerve injuries, perinatal asphyxia and even death. Among the maneuvers for delivery of the deeply impacted fetal head, the abdominovaginal delivery (push method) seems to be the most associated with maternal and neonatal complications. In the non-insinuated and floating fetal head, the internal podalic version followed by pelvic extraction differs from the reverse breech extraction (pull method). When the fetal head is high in the pelvis, the fetus is internally ejected before the extraction of its body segments, similar to the internal version performed in the vaginal delivery of the second twin with floating presentation of the fetus., Competing Interests: Conflicts of interest: None to declare, (© 2024. Federação Brasileira de Ginecologia e Obstetrícia. All rights reserved.)

Published
2024
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34. Phosphate availability conditions caspofungin tolerance, capsule attachment and titan cell formation in Cryptococcus neoformans .

Author

Qu X, Bhalla K, Horianopoulos LC, Hu G, Alcázar Magaña A, Foster LJ, Roque da Silva LB, Kretschmer M, and Kronstad JW

Abstract

There is an urgent need for new antifungal drugs to treat invasive fungal diseases. Unfortunately, the echinocandin drugs that are fungicidal against other important fungal pathogens are ineffective against Cryptococcus neoformans , the causative agent of life-threatening meningoencephalitis in immunocompromised people. Contributing mechanisms for echinocandin tolerance are emerging with connections to calcineurin signaling, the cell wall, and membrane composition. In this context, we discovered that a defect in phosphate uptake impairs the tolerance of C. neoformans to the echinocandin caspofungin. Our previous analysis of mutants lacking three high affinity phosphate transporters revealed reduced elaboration of the polysaccharide capsule and attenuated virulence in mice. We investigated the underlying mechanisms and found that loss of the transporters and altered phosphate availability influences the cell wall and membrane composition. These changes contribute to the shedding of capsule polysaccharide thus explaining the reduced size of capsules on mutants lacking the phosphate transporters. We also found an influence of the calcineurin pathway including calcium sensitivity and an involvement of the endoplasmic reticulum in the response to phosphate limitation. Furthermore, we identified membrane and lipid composition changes consistent with the role of phosphate in phospholipid biosynthesis and with previous studies implicating membrane integrity in caspofungin tolerance. Finally, we discovered a contribution of phosphate to titan cell formation, a cell type that displays modified cell wall and capsule composition. Overall, our analysis reinforces the importance of phosphate as a regulator of cell wall and membrane composition with implications for capsule attachment and antifungal drug susceptibility., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Qu, Bhalla, Horianopoulos, Hu, Alcázar Magaña, Foster, Roque da Silva, Kretschmer and Kronstad.)

Published
2024
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35. Influence of extended working hours and physical recovery on absenteeism in the footwear industry from a system dynamics model.

Author

Lucas REC, Merino EAD, da Silva LB, Leite WKDS, Norte Silva JM, and Rique Júnior JF

Abstract

Objectives . Work-related musculoskeletal disorders (WMSDs) are recurrent in the footwear industry, resulting in absenteeism. This study aimed to quantitatively analyze the influence of overtime work and physical recovery time on the occurrence of WMSD-related absenteeism using a system dynamics model. As ergonomic methods have limitations in quantitatively simulating the behavior of these relationships, the integration of computational modeling techniques has emerged as a methodological alternative to bridge this gap. Methods. An ergonomic work analysis (EWA) was developed in a production cell of a large company. A model of causal relationships (causal loop diagram) and a simulation model (flow and stock diagram) were then developed, where three scenarios for overtime and physical recovery time were analyzed. Results . Working an additional hour resulted in a 42% increase in physical overload, leading to 7.62 leave requests per year and 78.7 days of employee absenteeism. Increasing the physical recovery time by 15 min reduced the overload to 36.5%, resulting in 6.8 leave requests per year and 71.1 days of employee absenteeism. Conclusions. Properly managing excess workload and providing adequate physical recovery for professionals is necessary to mitigate the productivity impacts of absenteeism in the footwear industry.

Published
2024
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36. Analysis of the influence of occupational, sociodemographic and health factors on the demotivation of the intensivist.

Author

Vieira EMA, da Silva JMN, Leite WKDS, Oliveira RSG, and da Silva LB

Abstract

Introduction: Understanding motivation, identifying motivational factors of health professionals, and recognizing how managers and leaders can successfully motivate healthcare professionals is a growing concern., Objectives: To assess the occupational, sociodemographic, and health factors that influence the occurrence of demotivation in the intensive care unit professionals., Methods: We performed a cross-sectional study with health professionals from nine intensive care units in João Pessoa, Paraíba state, Brazil. Data were collected using an adapted version of the Health Care Establishment Questionnaire. We built a Logistic Regression model to analyze the influence of variables on the motivational state, and variables were selected by the Backward method. We used 80% of the sample for parameter estimation and the remaining 20% for testing and validation. We used the R software for the analyses, with a significance level of α ≤ 0.05., Results: We identify that the variable with the greatest power over the intensivist's demotivation was shift work (odds ratio [OR] = 4.215, p = 0.006). The number of symptoms (OR = 1.206, p = 0.000) and working time (OR = 1.080, p = 0.031) were also significant risk variables. When the three variables were combined, the professional's chance of feeling unmotivated increased by 38 times (OR = 38.99, p = 0.000)., Conclusions: Based on these results, it is possible to identify aspects that will require organizational adjustments so that intensivists remain satisfied and motivated., Competing Interests: Conflicts of interest: None

Published
2024
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37. Risk assessment due to natural radioactivity of stone dust and crushed stone Commercialized in construction stores in the state of Rio de Janeiro.

Author

Silva LB, Faria da Silva L, Orejuela COP, Mattos Barbosa C, Marzullo FL, Monteiro de Lima AM, and Silva AXD

Abstract

A systematic study of the distribution of the Naturally Occurring Radioactivity in stone dust and crushed stone, has been carried out with an objective of establishing reliable baseline data on the radiation level and hence to evaluate hazard indices approach and the production of radioactive heat (RHP) due to radiation exposure to the workers and to the inhabitants of the studied area. Twenty-six samples have been collected from different locations in the State of Rio de Janeiro (Brazil). To calculate the specific activity, gamma ray spectrometry and a detector of High Purity Germanium (HPGe; Canberra, 30% relative efficiency) was used. The activity concentration of 238 U, 226 Ra 232 Th and 40 K ranged from 29.3 ± 18.6 to 206.8 ± 21.5 Bq kg -1 , 30.3 ± 1.0 to 134.3 ± 1.8, 27.9 ± 0.7 to 86.2 ± 0.9 Bq kg -1 , and 734.9 ± 35.1 to 1204.8 ± 53.5 Bq kg -1 , respectively. The mean values of the I ex , I in , I γ , I α , A UI , I RP112Rn , I PA , I PI and I Yu indices were 0.68 ± 0.09, 0.92 ± 0.12, 0.93 ± 0.12, 0.43 ± 0.07, 0.88 ± 0.20, 1.25 ± 0.21, 0.34 ± 0.05, 0.75 ± 0.10, 0.63 ± 0.08 and 34. ± 6.31, respectively. The average radioactive heat production (RHP) of 2.01 ± 0.28 μ Wm -3 was above the values found in the literature, which may contribute to the heat flow in the study area because the raw materials that make up the samples showed a high value of environmental radioactivity. The Brazilian Hazard Index to assess the radiological risk of crushed stone and stone dust was created and the average value was 0.74 ± 0.10, a value below 1, which means only moderate control over the use of these materials, with no indication of restriction to the its use., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Published
2024
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38. Ergonomics, Health, and Perceptions about Remote Domestic Workposts: Study in Areas of City of João Pessoa, Paraíba, Brazil.

Author

Silva LB, Beserra Melo CJ, Lisboa de Souza AG, and de Oliveira LG

Subjects
Brazil, Humans, Adult, Male, Female, Middle Aged, SARS-CoV-2, Teleworking, Ergonomics, COVID-19
Abstract

Home office (HO) stands out as one of the most promising and popular forms of teleworking, especially after the COVID-19 pandemic. Therefore, many companies want to implement or maintain this working method, given its numerous advantages. However, there are adverse effects that are mainly related to physical and mental health. This article presents ergonomic analyses of HOs in neighborhoods considered heat islands. Temperature levels, extreme low-frequency non-ionizing radiation (ELF-NIR), illuminance, physical layout characteristics, and physiological parameters of teleworkers were measured. The results reveal that 92% of these professionals work 6 to 8 h daily with an ambient temperature between 25 and 30 °C, illumination levels in the range 11.20-290 Lux, and ELF-NIR > 0.4 µT. The majority of teleworkers are overweight (BMI > 24.9), and some of them have blood pressure higher than average values (129 mmHg for systolic and 84 mmHg for diastolic) in addition to a reduction in the number of red blood cells and hematocrits. Symptoms such as burning sensation, dryness, tired eyes, redness, itching, and photophobia (light sensitivity) show a 68.95% similarity. These HOs do not meet the required ergonomic and health standards.

Published
2024
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39. The role of fidgety movements and early motor repertoire in predicting mobility outcomes in infants with myelomeningocele.

Author

Utsch F, Silva LB, da Cunha Júnior AL, Alves EP, Diniz Silva CR, Vilaça DMF, and Moraes Antunes AA

Abstract

Objective: To describe fidgety movements and co-occurring movements and postures in infants with myelomeningocele (MMC) and their association with mobility at preschool ages., Methods: A retrospective cohort with early assessment via general movement assessment, followed by mobility assessment between 36 and 70 months of age., Results: Twelve infants were included; 12 of 12 had fidgety movements in the upper limbs, with seven exhibiting them also in the hips and three in both the hips and ankles. The presence of fidgety movements in the lower limbs, kicking, a non-flat posture, a non-monotonous movement character, and a non-absent age-adequate movement repertoire were independently associated with mobility using the Hoffer modified classification and functional mobility scale (FMS) at 5 and 50 m. An optimality score was calculated based on leg movements and postures, ranging from 0 to 10 points. Infants who scored at least 4 points achieved household ambulation and FMS (5 m) of at least level 4. Community ambulation and an FMS (50 m) of level 5 were achieved with a score of at least 7.5., Conclusions: Assessing fidgety movements with other leg movements and postures in infants with MMC provided relevant information that could potentially predict mobility at preschool age and thus could be used for early intervention planning., Competing Interests: Declaration of competing interest This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. No declarations of interest, however, Fabiana Utsch is a licensed tutor with the General Movements Trust., (© 2024 Published by Elsevier Ltd on behalf of European Paediatric Neurology Society.)

Published
2024
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40. Medium and Long-Term Weight Loss After Revisional Bariatric Surgery: A Systematic Review and Meta-Analysis.

Author

Bastos ELS, Salgado W Jr, Dantas ACB, Onzi TR, Silva LB, Albano Á, Tristão LS, Dos Santos CL, Silvinato A, and Bernardo WM

Abstract

Despite the current increase in revisional bariatric surgery (RBS), data on the sustainability of weight loss remain unclear. A systematic review and meta-analysis were performed to assess weight loss outcomes in adult patients undergoing RBS with follow-up > 2 years. Twenty-eight observational studies (n = 2213 patients) were included. The %TWL was 27.2 (95%CI = 23.7 to 30.6), and there was a drop in BMI of 10.2 kg/m 2 (95%CI =  - 11.6 to - 8.7). The %EWL was 54.8 (95%CI = 47.2 to 62.4) but with a high risk of publication bias (Egger's test = 0.003). The overall quality of evidence was very low. Our data reinforce that current evidence on RBS is mainly based on low-quality observational studies, and further higher-quality studies are needed to support evidence-based practice., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Published
2024
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41. Vertical transmission of chikungunya virus: a worldwide concern.

Author

Faria BS, da Silva LB, Avelar CFR, de Morais PAS, and Bentes AA

Subjects
Humans, Infant, Newborn, Female, Pregnancy, Chikungunya virus, Fatal Outcome, Pregnancy Complications, Infectious virology, Male, Chikungunya Fever transmission, Chikungunya Fever diagnosis, Infectious Disease Transmission, Vertical
Abstract

The Chikungunya Virus (CHIKV) already has endemic circulation in about 100 countries and the number of infected patients increases every year, due to the effectiveness of the vector and human universal susceptibility to infection. The virus can also be transmitted from mother to child, more frequently intrapartum. About 50 % of neonates with CHIKV symptoms will have neurodevelopmental delay. It is therefore an infection of worldwide concern with a great impact on people's quality of life. The objective of this work is to describe two cases of confirmed vertical transmission by chikungunya virus, one of them with intrauterine infection and death of the neonate. Neonates with vertical chikungunya infection may present with clinical sepsis in the first few days of life, which is why this is a very important diagnosis, especially during outbreaks of the infection., Competing Interests: Conflicts of interest The authors declare no conflicts of interest., (Copyright © 2024 Sociedade Brasileira de Infectologia. Published by Elsevier España, S.L.U. All rights reserved.)

Published
2024
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42. Sleep deprivation induces late deleterious effects in a pharmacological model of Parkinsonism.

Author

Lopes-Silva LB, Cunha DMG, Lima AC, Bioni VS, Gonçalves N, Kurita JPF, Wuo-Silva R, and Silva RH

Subjects
Animals, Male, Mice, Catalepsy chemically induced, Oxidative Stress physiology, Oxidative Stress drug effects, Tyrosine 3-Monooxygenase metabolism, Motor Activity physiology, Motor Activity drug effects, Recognition, Psychology physiology, Recognition, Psychology drug effects, Anhedonia physiology, Anhedonia drug effects, Reserpine pharmacology, Sleep Deprivation complications, Disease Models, Animal, Parkinsonian Disorders chemically induced, Parkinsonian Disorders physiopathology
Abstract

Parkinson's disease is a degenerative, chronic and progressive disease, characterized by motor dysfunctions. Patients also exhibit non-motor symptoms, such as affective and sleep disorders. Sleep disorders can potentiate clinical and neuropathological features and lead to worse prognosis. The goal of this study was to evaluate the effects of sleep deprivation (SD) in mice submitted to a progressive pharmacological model of Parkinsonism (chronic administration with a low dose of reserpine). Male Swiss mice received 20 injections of reserpine (0.1 mg/kg) or vehicle, on alternate days. SD was applied before or during reserpine treatment and was performed by gentle handling for 6 h per day for 10 consecutive days. Animals were submitted to motor and non-motor behavioral assessments and neurochemical evaluations. Locomotion was increased by SD and decreased by reserpine treatment. SD during treatment delayed the onset of catalepsy, but SD prior to treatment potentiated reserpine-induced catalepsy. Thus, although SD induced an apparent beneficial effect on motor parameters, a delayed deleterious effect on alterations induced by reserpine was found. In the object recognition test, both SD and reserpine treatment produced cognitive deficits. In addition, the association between SD and reserpine induced anhedonic-like behavior. Finally, an increase in oxidative stress was found in hippocampus of mice subjected to SD, and tyrosine hydroxylase immunoreactivity was reduced in substantia nigra of reserpine-treated animals. Results point to a possible late effect of SD, aggravating the deficits in mice submitted to the reserpine progressive model of PD., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Published
2024
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43. Breech birth care: Number 1 - 2024.

Author

Alves ÁLL, Nozaki AM, Polido CBA, da Silva LB, and Knobel R

Subjects
Humans, Pregnancy, Female, Delivery, Obstetric, Brazil, Breech Presentation therapy
Abstract

Competing Interests: Conflicts of interest: none to declare.

Published
2024
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44. "Even if we are the caring hand": Black doctors and structural racism in the context of primary health care.

Author

Silva LB, Campos DS, Araújo MVR, and Reis RS

Subjects
Female, Humans, Brazil, Upper Extremity, Primary Health Care, Systemic Racism, Physicians
Abstract

This study scrutinizes structural racism's influence on the training and work of Black professionals in primary health care (PHC) in Rio de Janeiro, particularly focusing on the experiences of Black female physicians. Employing a qualitative approach via a Focus Group, conducted in November 2022, we adopted symbolic interactionism to interpret racism-related experiences. Our findings encompass two primary dimensions: the manifestation of structural and institutional racism within the Unified Health System (SUS), and how racism permeates health work processes and consequences. Results highlight enduring impacts, spanning education to PHC roles, hindering healthcare process recalibration. Participants identify institutional and structural racism, from managerial neglect to territorial violence and physician scarcity, constraining comprehensive care. It is crucial to unveil and grasp racism's structural essence within healthcare, aligned with the vision of health as a fundamental right.

Published
2024
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45. Quality of systematic reviews on the treatment of vesiculobullous skin diseases. A meta-epidemiological study.

Author

Sá KMM, Rodrigues JC, da Silva LB, Santos GM, Colovati MES, and Martimbianco ALC

Subjects
Humans, Systematic Reviews as Topic, Epidemiologic Studies, Pemphigus drug therapy, Pemphigus epidemiology
Abstract

Background: Systematic reviews of Randomized Controlled Trials (RCTs) are considered high-level evidence to support a decision on therapeutic interventions, and their methodological quality is essential to provide reliable and applicable results., Objective: This meta-epidemiological study aimed to map and critically appraise systematic reviews assessing treatments for vesiculobullous skin diseases., Methods: We conducted a comprehensive search strategy on MEDLINE (via Pubmed) in December 2022 without restrictions to find systematic reviews evaluating pharmacological interventions for vesiculobullous skin diseases. The methodological quality was assessed using the AMSTAR-2 tool, and additional information was extracted. We identified nine systematic reviews published between 2002 and 2021, seven assessing pemphigus., Results: According to the AMSTAR-2 tool, 55.6% were classified as critically low quality, 22.2% as moderate quality, 11.1% as low and 11.1% as high quality. No review assessed the certainty of the evidence (GRADE); 86% of pemphigus reviews had at least two overlapping RCTs. There were some limitations regarding methodological flaws and the AMSTAR-2 tool use CONCLUSIONS: These findings reveal a frail methodological quality of systematic reviews about vesiculobullous diseases treatment that may impact the results. Therefore, methodological rigor is mandatory for future systematic reviews to avoid duplication of effort and increase the certainty of the evidence supporting decision-making., (Copyright © 2023. Published by Elsevier España, S.L.U.)

Published
2024
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46. Animal Approaches to Studying Risk Factors for Parkinson's Disease: A Narrative Review.

Author

Silva RH, Lopes-Silva LB, Cunha DG, Becegato M, Ribeiro AM, and Santos JR

Abstract

Despite recent efforts to search for biomarkers for the pre-symptomatic diagnosis of Parkinson's disease (PD), the presence of risk factors, prodromal signs, and family history still support the classification of individuals at risk for this disease. Human epidemiological studies are useful in this search but fail to provide causality. The study of well-known risk factors for PD in animal models can help elucidate mechanisms related to the disease's etiology and contribute to future prevention or treatment approaches. This narrative review aims to discuss animal studies that investigated four of the main risk factors and/or prodromal signs related to PD: advanced age, male sex, sleep alterations, and depression. Different databases were used to search the studies, which were included based on their relevance to the topic. Although still in a reduced number, such studies are of great relevance in the search for evidence that leads to a possible early diagnosis and improvements in methods of prevention and treatment.

Published
2024
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47. Findaureus: An open-source application for locating Staphylococcus aureus in fluorescence-labelled infected bone tissue slices.

Author

Mandal S, Tannert A, Löffler B, Neugebauer U, and Silva LB

Subjects
Mice, Animals, Humans, Bacteria, Microscopy, Fluorescence, Bone and Bones diagnostic imaging, Staphylococcus aureus, Staphylococcal Infections diagnostic imaging, Staphylococcal Infections microbiology
Abstract

Staphylococcus aureus (S. aureus) is a facultative pathogenic bacterium that can cause infections in various tissue types in humans. Fluorescence imaging techniques have been employed to visualize the bacteria in ex-vivo samples mostly in research, aiding in the understanding of the etiology of the pathogen. However, the multispectral images generated from fluorescence microscopes are complex, making it difficult to locate bacteria across image files, especially in consecutive planes with different imaging depths. To address this issue, we present Findaureus, an open-source application specifically designed to locate and extract critical information about bacteria, especially S. aureus. Due to the limited availability of datasets, we tested the application on a dataset comprising fluorescence-labelled infected mouse bone tissue images, achieving an accuracy of 95%. We compared Findaureus with other state-of-the-art image analysis tools and found that it performed better, given its specificity toward bacteria localization. The proposed approach has the potential to aid in medical research of bone infections and can be extended to other tissue and bacteria types in the future., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Mandal et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Published
2024
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48. Ordered mesoporous silicas for potential applications in solid vaccine formulations.

Author

Miranda MCR, Nunes CM, Santos LF, da Silva LB, de Jesus VR, Filho NA, Pedro JAF, Lopes JLS, Oliveira CLP, Fantini MCA, Cardoso JS, Trezena AG, Ribeiro OG, Sant'Anna OA, Tino-De-Franco M, and Martins TS

Subjects
Silicon Dioxide chemistry, Vaccines
Abstract

In an effort to develop efficient vaccine formulations, the use of ordered mesoporous silica (SBA-15) as an antigen carrier has been investigated. SBA-15 has required properties such as high surface area and pore volume, including narrow pore size distribution to protect antigens inside its matrix. This study aimed to examine the impact of solvent removal methods, specifically freeze-drying and evaporation on the intrinsic properties of an immunogenic complex. The immunogenic complexes, synthesized and incorporated with BSA, were characterized by various physicochemical techniques. Small Angle X-ray Scattering measurements revealed the characteristic reflections associated to pure SBA-15, indicating the preservation of the silica mesostructured following BSA incorporation and the formation of BSA aggregates within the macropore region. Nitrogen Adsorption Isotherm measurements demonstrated a decrease in surface area and pore volume for all samples, indicating that the BSA was incorporated into the SBA-15 matrix. Fluorescence spectroscopy evidenced that the tryptophan residues in BSA inside SBA-15 or in solution displayed similar spectra, showing the preservation of the aromatic residues' environment. The Circular Dichroism spectra of BSA in both conditions suggest the preservation of its native secondary structure after the encapsulation process. The immunogenic analysis with the detection of anti-BSA IgG did not give any significant difference between the non-dried, freeze-dried or evaporated groups. However, all groups containing BSA and SBA-15 showed results almost three times higher than the groups with pure BSA (control group). These facts indicate that none of the BSA incorporation methods interfered with the immunogenicity of the complex. In particular, the freeze-dried process is regularly used in the pharmaceutical industry, therefore its adequacy to produce immunogenic complexes was proved Furthermore, the results showed that SBA-15 increased the immunogenic activity of BSA., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Tereza S. Martins reports financial support and equipment, drugs, or supplies were provided by State of Sao Paulo Research Foundation. Tereza S. Martins reports financial support and equipment, drugs, or supplies were provided by Coordination of Higher Education Personnel Improvement. Osvaldo A. Sant Anna reports financial support and equipment, drugs, or supplies were provided by State of Sao Paulo Research Foundation. Marcia C.A. Fantini reports financial support and equipment, drugs, or supplies were provided by State of Sao Paulo Research Foundation. Marcia C.A. Fantini reports financial support and equipment, drugs, or supplies were provided by National Council for Scientific and Technological Development. Cristiano L.P. Oliveira reports financial support and equipment, drugs, or supplies were provided by State of Sao Paulo Research Foundation. Cristiano L. P. Oliveira reports financial support and equipment, drugs, or supplies were provided by National Council for Scientific and Technological Development. Jose L.S. Lopes reports financial support and equipment, drugs, or supplies were provided by State of Sao Paulo Research Foundation. Matheus C. R. Miranda reports financial support was provided by State of Sao Paulo Research Foundation. Jessica A. F. Pedro reports financial support was provided by State of Sao Paulo Research Foundation. Leonardo B. da Silva reports financial support was provided by Coordination of Higher Education Personnel Improvement. Carmen M. Nunes reports financial support was provided by National Council for Scientific and Technological Development. Luana F. Santos reports financial support was provided by National Council for Scientific and Technological Development., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Published
2024
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49. Influence of environmental variables on students' cognitive performance in indoor higher education environments.

Author

Lucas REC, da Silva LB, de Souza EL, Leite WKDS, and da Silva JMN

Subjects
Humans, Brazil, Female, Male, Universities, Temperature, Environment, Humidity, Lighting, Adult, Students psychology, Students statistics & numerical data, Cognition
Abstract

Background: Educational environments can have environmental conditions that are incompatible with the needs of students, compromising their well-being and affecting their performance., Objective: To identify the environmental variables that influence the performance of university students and measure this influence through an experiment in indoor environments., Methods: The study applied an experimental methodology for three consecutive days in seven educational environments located in different regions of Brazil, measuring the environ-mental conditions, the students' perception of the environment, and their cognitive performance. The impact of environmental variables and environmental perception on student performance was analyzed using Generalized Linear Models and a Structural Equation Model., Results: Students who took the test at air temperatures between 22.4°C and 24.7°C had a 74.20% chance of performing better than those outside this range. Air temperatures between 26.2°C and 29°C were associated with an 86% chance of taking less time to complete the test. High illuminance levels increased the chance of taking longer to answer the test by 41.7%., Conclusions: Three environmental variables (relative humidity, lighting and air temperature) and two perceptual dimensions (light and thermal perception) directly influence student performance.

Published
2024
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50. Antibacterial Activity of Epigallocatechin-3-gallate (EGCG) Loaded Lipid-chitosan Hybrid Nanoparticle against Planktonic Microorganisms.

Author

Moreno APD, Marcato PD, Silva LB, Salvador SLS, Arco MCGD, Moraes JCB, Silva RSD, and Rossi A

Subjects
Streptococcus sobrinus drug effects, Lacticaseibacillus casei drug effects, Lipids chemistry, Plankton drug effects, Dental Caries microbiology, Dental Caries prevention & control, Drug Carriers chemistry, Particle Size, Emulsions, Sonication, Catechin analogs & derivatives, Catechin pharmacology, Catechin chemistry, Chitosan chemistry, Chitosan pharmacology, Streptococcus mutans drug effects, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents chemistry, Nanoparticles chemistry, Microbial Sensitivity Tests
Abstract

Epigallocatechin-3-gallate (EGCG), a polyphenol derived from Green Tea, is one of the sources of natural bioactive compounds which are currently being developed as medicinal ingredients. Besides other biological activities, this natural compound exhibits anti-cariogenic effects. However, EGCG has low physical-chemical stability and poor bioavailability. Thus, the purpose of this study was to develop and characterize lipid-chitosan hybrid nanoparticle with EGCG and to evaluate its in vitro activity against cariogenic planktonic microorganisms. Lipid-chitosan hybrid nanoparticle (LCHNP-EGCG) were prepared by emulsion and sonication method in one step and characterized according to diameter, polydispersity index (PdI), zeta potential (ZP), encapsulation efficiency (EE), mucoadhesion capacity and morphology. Strains of Streptococcus mutans, Streptococcus sobrinus and Lactobacillus casei were treated with LCHNP- EGCG, and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated. LCHNP-EGCG exhibited a size of 217.3 ± 5.1 nm with a low polydispersity index (0.17) and positive zeta potential indicating the presence of chitosan on the lipid nanoparticle surface (+33.7 mV). The LCHNP-EGCG showed a spherical morphology, high stability and a mucoadhesive property due to the presence of chitosan coating. In addition, the EGCG encapsulation efficiency was 96%. A reduction of almost 15-fold in the MIC and MBC against the strains was observed when EGCG was encapsulated in LCHNP, indicating the potential of EGCG encapsulation in lipid-polymer hybrid nanoparticles. Taking the results together, the LCHNP-EGCG could be an interesting system to use in dental care due to their nanometric size, mucoadhesive properties high antibacterial activity against relevant planktonic microorganisms.

Published
2024
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